Depleted of resources, Voyager limps into the vicinity of a class Y planet, known informally as a "demon" class planet. Though standard Starfleet procedure calls for total avoidance of the hostile environment of these planets, Janeway and the crew are left with no choice but to try to improvise a way to adapt the planet's natural resources to power Voyager. Tom and Harry are the first away team to visit the planet, and they fail to report back. But the rescue team commanded by Chakotay finds both of them in perfect health - and capable of breathing freely in the deadly atmosphere of the planet. However, transporting the two back to Voyager almost proves fatal, leading the Doctor to believe that anyone who has visited this class Y planet can never leave it again.
